1. Field of the Invention
This invention relates to an orthosis. More specifically, it relates to a laterally applied orthosis having a flexible stiffener.
2. Description of the Related Art
Patients that have neurological disorders such as cerebral palsy and multiple sclerosis, muscular disorders, stroke victims, or persons with spinal cord injuries often uncontrollably contract their joints in flexion, which can cause the patients to lose range of motion in their joints. Common joints that are affected by patients having these conditions include wrist joints and finger joints, foot, toe, and ankle joints, hip joints, elbow joints, and knee joints. In an attempt to treat or otherwise alleviate the potential loss of range of motion due to conditions like those set forth above, doctors and physical therapists often secure an orthosis or splint across the affected joint to prevent uncontrollable flexion of the joint by stretching the joint to a desired position. The orthosis may be moved to a series of desired positions to stretch the joint and hopefully prevent a loss of range of motion.
Many different types of orthoses have been developed that stretch joints to a desired position thereby preventing patients wearing the orthoses from uncontrollably contracting their joints in flexion. For example, U.S. Pat. No. 6,261,253 to Katzin discloses a hand orthosis that limits finger and wrist flexion with a steel stiffener that provides a static resistance to the user. The stiffener is plastically deformed into the desired position to conform to the shape of the joint and surrounding limbs. However, the stiffener is made of material such that it will resist forces to which it is normally subjected when worn by a patient. That is, during contracture, the patient is unable to move the stiffener during use such that the stiffener provides a static resistance to the joint. While this property is useful in many circumstances, the needs of certain patients require a different type of stiffener.
The assignee of the present application has also developed knee and elbow orthoses for treatment of undesirable flexural contractions of those joints. These knee and elbow orthoses utilize goniometers which are adjustable to allow a certain degree of joint movement. For example, if zero degrees represents the angle of a patient's arm or leg when it is straight, then the goniometer can be adjusted so that the patient can only move his or her arm or leg a predetermined number of degrees freely within the range of movement allowed by the goniometer. For some patients it is undesirable to use an orthosis that allows this type of movement, even if it is only within a certain range.
Thus, while orthoses have been used to treat or alleviate the symptoms of uncontrollable joint flexion, there is a need for the type of orthosis that is disclosed in the present application.